dailysudoku.com

[jratliff]

Hi everyone. This puzzle came with only one 1 and one 2 and I have been unable to place another leaving very few single pairs in the candidate lists. I've tried all the basic techniques, x-wings, swordfish, and y-wings. I've looked for hidden pairs, triples and quads and am just stuck.

The original puzzle had 25 cells to begin with and I've filled in only 8. I entered what I have into a software solver to be sure it is valid.

023 008 409
040 300 085
005 904 300
500 000 894
000 040 000
064 080 007
402 007 900
370 406 010
000 800 740

Thank you very much for any assistance.

jratliff

[Bluey]

As 2 has to be in R4 columns 4, 5 or 6 (as 2 is already in C2 and 3) 2 cannot be in R5 C4 or 6 or in R6 C4 or 6.

As 6 has to be in R9 C1 or C3 (as 6 is already in C2 and R 6 cannot be in R9 C9

C4 now has a pair of 1,5 in R6 & 7, so delete 1&5 in C4 R1, C4 R4 and C4 R5. This gives a new pair of 6,7 in C4 at R1 and 5.
Therefore C4 R4 must be 2.
C5 R1 must now be 5, and C1 R1 must be 1, C2 R3 must be 8 and so on.
Hope this helps!

[jratliff]

Hey Bluey. Thanks a lot. That did the trick...

...now I can continue with my life.

Cheers.